your position is our focus
6.3 System Sensitivity Test
The
best
way
to
test
the
sensitivity
of
a
GPS
device
is
with
the
use
of
a
1-channel
GPS
simulator.
It
assures
reliable
and
constant
signals
at
every
measurement.
Figure 104: 1-channel GPS simulator
u-blox
mmends
the
following
Single-Channel
GPS
Simulator:
GSS6100
Communications
Positioning
Technology
reco
•
Spirent
Spirent
(previously
GSS
Global
Simulation
Systems)
www.positioningtechnology.co.uk
3.
Power
up
the
DUT
(Device
Under
Test)
and
allow
enough
time
for
the
acquisition
4.
Read
the
C/No
value
from
the
NMEA
GSV
or
the
UBX-NAV-SVINFO
messag (e.g.
with
u-center
AE)
5.
Reduce
the
power
level
by
10dB
and
read
the
C/No
value
again
6.
Compare
the
results
to
a
“Golden
Device”
or
an
ANTARIS
®
4
GPS
EvalKit.
6.3.2 ‘Go/No go’ tests for integrated devices
osition
with excellent visibility
(HDOP
<
3.0).
Let
the
ngth
with
a
“Golden
Device”.
Note
As
the
electro-magnetic
field
of
a
redistribution
antenna
is
not
homogenous,
indoor
tests
are
in
most
cases
not
reliable.
These
kind
of
tests
may
be
useful
as
a
‘go/no
go’
test
but
not
for
sensitivity
measurements.
6.3.1
Guidelines for Sensitivity Tests
1.
Connect
a
1-channel
GPS
simulator
to
the
OEM
product
2.
Choose
the
power
level
in
a
way
that
the
“Golden
Device”
would
report
a
C/No
ratio
of
45
dBHz
e
The
best
test
is
to
bring
the
device
to
an
outdoor
p
receiver
acquire
satellites
and
compare
the
signal
stre
GPS
Modules
-
System
Integration
Manual
(SIM)
(incl.
Reference
Design)
Product
Testing
GPS.G4-MS4-05007-A1
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